Bell Gardens outlines operation, maintenance concerns for new subsurface cistern at Ford Park

City staff and project consultants presented an update on the John Hansen Ford Park infiltration system on Jan. 12, describing the constructed subsurface storage and infiltration system, early operational experience and maintenance needs.

Public Works Director Bernie Aniguez and project consultant/designer Desi Alvarez described the facility as a 21.5 acre-foot (roughly 7 million gallons) buried infiltration basin composed of stacked precast concrete galleries placed beneath the ball fields at John Hansen Ford Park. "It's a 21 and a half acre foot retention and infiltration basin that's buried under the ball fields," Alvarez said, walking the council through the main components: a diversion slot in the storm drain, a gate valve and splitter, two large hydrodynamic separators for pretreatment, and a precast cistern where the water infiltrates to recharge groundwater.

Alvarez and Aniguez emphasized that the system captures 100% of dry-weather flows from the targeted watershed and captures the first flush during storms (the portion of a storm that typically carries higher pollutant loads). "During dry weather, you had a 100% capture," Alvarez said. Project staff noted the system became operational in 2025 and captured its first storm in April 2025.

Presenters detailed operational challenges observed during initial operation: sediment and debris accumulating in the diversion structure and downstream sections, finer sediments breaking through pretreatment and collecting in the cistern, and flow-meter and instrumentation calibration issues for low (dry-weather) flow rates. Alvarez said the cistern has taken longer than anticipated to drain in some events — roughly "28 days plus or minus" in an early observation — and staff are still collecting data to establish a reliable maintenance schedule.

Staff reported the construction phase cost was a little over $19 million (design, construction management and construction). Combined with other park and aquatics work (estimated at $31 million for aquatics and park improvements), the presenter described roughly $50 million in overall improvements to the park area. For ongoing operations and maintenance, staff estimated an initial monitoring and maintenance budget of about $100,000 per year to cover instrumentation, cleaning, and periodic sediment-removal activities; Bell Gardens' estimated share under the agreed cost-allocation formula was $12,800 annually, to be funded from municipal Measure W funds rather than general fund dollars.

Council members asked about public visibility and education opportunities; staff suggested signage or periodic public tours of the electrical/instrumentation room and demonstrated maintenance activities as learning opportunities for students and residents. Staff recommended continued monitoring, instrument retrofits (including installing a meter in the pipe for better dry-weather flow measurement), and adoption of a maintenance MOU among the seven watershed cities that participate in the project.

Why it matters: The infiltration system is intended to reduce pollutant loads to the Rio Hondo channel and the Los Angeles River, while augmenting local groundwater supplies in the Central Basin. Staff framed the system as a pilot and described it as a regional asset shared across seven cities; long-term performance and O&M needs are still being established.

The council voted to receive and file the update by unanimous roll-call vote.